Can flange straightening machine



Patented Dec. 13., 1949 AUNITED STATES PATENT OFFICE CAN FLANGE STRAIGHTENING MACHINE Howard B. Peterson, San Francisco, Calif., as-

signor to American Can Company, New York, N. Y., a corporation of New Jersey Application January 26, 1948, Serial No. 4,292

7 Claims.

The present invention relates to container or can making machines and has particular reference to a machine for straightening or reforming the flanges of containers or cans which have become distorted during handling.

In the manufacture of certain cans made of tin plate or the like sheet metal, a flange is provided on the ends of the can body for securing the end or closure members in place by an interfolded joint such as the well known double seam or the like. This ange on the can body is formed with a predetermined cross-sectional contour to properly t with the can end member to be secured to the body.

During the manufacture of these cans, they are transferred from one machine to another, and occasionally during these transfers, the flanges become dented or distorted. Such a dent or distortion of the can iiange prevents proper seating of the ange against the end closure and hence when the closure is interfolded with the flange in sealing the can, a leaky seam may result and the can is thereby rendered useless.

The instant invention contemplates overcoming these difficulties by the provision of a machine for straightening can flanges that have become dented or otherwise distorted.

An object of the invention is the provision of a can ange straightening machine wherein dents or other distortions in the flange of a can or can body may be readily removed with the result that a straightened flange will properly flt against a closure member when applied to the can and may be readily interfolded therewith to obtain a strong and tight seam.

Another object is the provision of such a flange straightening machine wherein the straightening of the iiange on a can or can body is effected by angularly disposed jaws which are actuated under fluid pressure so as to provide a sturdy machine which can be easily operated by a foot treadle or the like and thus leave the hands of the operator free for the handling of the cans.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure 1 is a top plan view of a machine embodying the instant invention, with parts broken away;

Fig. 2 is a sectional view taken substantially 2 along the line 2-2 in Fig. 1, with parts broken away;

Fig. 3 is a horizontal section taken substantially along the line 3--3 in Fig. 2; and

Fig. 4 is a sectional detail of one of the machine parts, the View being taken substantially along the line 4 4 in Fig. 2, with a portion broken away.

As a preferred embodiment of the instant invention, the drawings illustrate a semiautomatic machine for straightening a flange A of a cylindrical sheet metal can B (Fig. 2), although the invention is equally well adapted to other sizes and shapes of cans or can bodies of' various materials and even to other articles having portions which require a straightening operation. In the illustrated machine the cans B are handled manually. For a flange straightening operation a can B is telescoped in an inverted position over a vertical stationary cylindrical post or anvil II (Figs. 1 and 2) which is secured by a bolt I2 to a frame I3 which constitutes the main frame of the machine.

The upper end of the anvil II preferably is slightly tapered to facilitate placing of the can on the post and to expedite its removal therefrom. Immediately below this tapered portion, the anvil II is formed with a backing-up or support section I4 which is substantially the same size as the interior of the can to be received. This support section terminates adjacent a curved, flanges straightening shoulder I5 formed on the post and against which the distorted flange A to be straightened is seated when a can B is placed on the anvil as best shown in Fig. 2. The curvature or shape of the shoulder l5 is substantially that of a correct or proper flange A.

Straightening of a ange A of a can B on the anvil I I preferably is effected by a set of straightening jaws I8 which are movable toward and' away from the anvil at an angle thereto. There are three of these jaws I8 distributed equally around the anvil II and disposed in a plane normal to the anvil. The inner edges of these jaws are curved to flt around the anvil and when in ange straightening position as shown in Figs. 1 and 2, they entirely surround the anvil. These curved edges are tapered inwardly and are rounded off with a cross-sectional curvature to rlt the cross-sectional curvature of the ange straightening shoulder I5.

The straightening jaws I8 are bolted to support blocks 20 which are secured to the tops of angularly disposed support rods 2| which are slldeable in bearings 22 formed in the frame I3. There are three of these rods 2l and their lower ends converge toward the center of the frame I3. The rods are normally held in a raised position by a plurality of compression springs 23 which are located in blind bores 24 formed in the frame I3 adjacent the upper ends of the rods 2|. There are two of these springs 23 for each rod, as shown in Fig. l, and they are interposed between the bottoms of the blind bores 24 and the support blocks 20 secured to the upper ends of the rods. The springs hold the jaws in an expanded position away from the anvil as shown in dotted lines in Fig. 2 to permit placing and removal of the cans B on and from the anvil.

The converging lower ends of the support' rods 2| are cut away on twoV sides as best shown' in Figs. 3 and 4 and thus form narrow I-shaped webs 2'! interposed between vupper and lower horizontal and laterally extending ledges 23, 23. These I-shaped converging lower ends of the support rods 2| extend into a vertically disposed cylinder 3| formed integrally with the rod bearings 22 as a part of the frame I3. A free piston 3`2' is mated within the cylinder.

The side of the piston adjacent its lower end is formed withthree peripherally spaced slots 3 3 into whichthe webs 21 of the support rods 2| extend. This web and slot connection between the rods and the piston hold the rods against turning in their slide bearings 22 and thus retain the jaws I8 in proper radial position relative to the anvil The lower end of the piston adjacent the slots 33 seats against the ledges' 29 on the rods 2| as shown in Fig. 2.

Theupper end of thepiston carries a-cup shaped washer 35 made of leather or other suitable washer material.

The cylinder 3| at its lower end is open. Adjacent its'upper end, the' cylinder is'in communication with a channel 37 formed inthe frame I3 and which connects Witha pipe or tube 38 threadedly engaged in the frame". Thispipe may be of any suitable length. Its opposite end isV connectedy to the outlet side ofy a manually operable three way Valve 4| of any suitable commercial type having an inlet and an outlet and an atmosphere port 42 and a springcontrolled push button or operating handle 43. The'inlet side of the valve`4|` is'c'onncted'toa pipe. 44 which leads to any suitable sourceof' iiuid under pressure, such as compressed air, gas; steam, oil or other medium. A spring, housed within the valve, keeps the operating handle '43 normally in a rais'edposition as shown in Fig. 2. In this position of the handle, the' inlet of the valve is closed and the interior of the cylinder 3| is in communication with the outside atmosphere by way of the channelu'l, pipe 38, the outlet of the valve and the atmosph'ere port 42. The valve preferably is'located on the floor adjacent the machine where it can be readily operated by the foot of the operator.

In the operation of the machine, the operator places an inverted can B on Vthe anvil |I, with the ange A of the can against the flange straightening shoulder l as shown in Fig. L2. The operator then steps on the valve handle 43 anddepresses it. This 'closes the atmosphere port 42 in the valve and opens the inletof the valve while also leaving its-outlet open". In this position of'the valve, fluid under pressure from the pipe 44 flows through `the valve, the pipeY 38, and channel 3'! and enters the cylinder 3 I. This 'entrine uid exerts its' force` against theY pistton washer and thus forces the piston down to the lower end of the cylinder as shown in Fig. 2.

During its downward travel, the piston, acting on the ledges 29 of the jaw support rods 2| forces the rods simultaneously downwardly and inwardly against the resistance of their springs 23. This angular movement of the rods draws the' ange straightening jaws I8 downwardly and inwardly from the position shown in dotted lines in Fig. 2 to the position shown in full lines in that figure and thus presses the inner curved edges of the jaws against the can flange A. This action is more of a hammer blow against the flange A thanthat of a squeezing action, and thus the flange of the can is compressed against the straightening shoulder I5. Any dents or other distortion in or of the flange is thereby hammered or ironed out to the true cross-sectional and peripheral curvature of the flange and the iflange is thus straightened for the subsequent reception of its end closure member.

If more than one hammer blow is required to effect complete straightening of the flange, this may be readily accomplished by repeated opening and closing of the valve 4|.

When the valve 4i Vis opened, by release of the operating handle 43, the spring within the valve immediately lifts thehandle and this cuts 30; on the flow of fluid from the pipe 44 and opens the cylinder Si to the atmosphere by way of the port 42 as hereinbefore explained. The fluid pressure within the cylinder 3| is thereby dissipated and the springs 23 thereupon lift the actuating rods 2 i' and return them to their original position; The upward travel of the rods withdraws the jaws I3 from the ange of the can B` and also raises the piston 32 in its cylinder 3| in readiness for a repeat action. The

:can B with its straightened flange A is thereupon removed manually. This completes a cycle of operation of the machine.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing discription, and it will be apparent that various changes may be made in the form, constructionand arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

l. In aV machine for straightening the flanges of cans, the combination of a frame, an anvil mounted on said frame for suporting a can, said anvil having a verticalbacking-up support wall merging into a curved shoulder against whichpthe flange of the can engages for the straightening operation, a plurality of Bange straightening jaws surrounding said anvil, support means for each jaw mounted in said frame and disposed at an angleto the backing-up wall and curved shoulder of saidanvilfornormally supporting said jaws in spa-ced and expanded position relative to said anvil shoulder, and means formoving said support meansalong their angular support axes `for shifting said jaws inwardly atan angle to 'said anvil and into' engagement with the' flange of the can on said anvilA for straightening the ilange against the backing'wall and curved shoulder on' said anvil.

2. In' 'a machine for straightening the flanges of cans, the combination of a frame, an anvil mounted on'said frame for supportinga can in an inverted position, said anvil having a shoulder against which the ange of the can engages for the straightening operation, a plurality of support rods mounted in said frame and having sliding movement along inclined axes outside of said anvil, a plurality of flange straightening jaws each jaw mounted on and secured to the upper end of a said support rod, said jaws surrounding said anvil, means for shifting said jaws downwardly and inwardly at an angle to said anvil by moving said support rods along their inclined axes to bring the jaws into engagement with the flange of the can on said anvil for straightening the flange against the shoulder on said anvil, and independent means for returning said jaws upwardly and outwardly to release them from s-aid can ange.

3. In a machine for straightening the flanges of cans, the combination of a frame, an anvil mounted on said frame for supporting a can in an inverted position, said anvil having a shoulder against which the flange of the can engages for the straightening operation, a plurality of flange straightening jaws surrounding said anvil, a plurality of support rods slideable in said frame and disposed at an angle to said anvil for sup porting said jaws, and means for moving said rods simultaneously for shifting said jaws downwardly and inwardly at an angle to said anvil and into engagement with the flange of the can on said anvil for straightening the flange against the shoulder on said anvil.

4 In a machine for straightening the anges of cans, the combination of a frame, an anvil mounted on said frame for supporting a can in an inverted position, said anvil having a shoulder against which the ange of the can engages for the straightening operation, a plurality of iiange straightening jaws surr-ounding said anvil, a plurality of support rods slideable in said frame and converging toward each other at an angle to said anvil for supporting said jaws, and means for moving said rods simultaneously for shifting said jaws downwardly and inwardly at an angle to said anvil and into engagement with the flange of the can on said anvil for straightening the ange against the shoulder on said anvil.

5. In a machine for straightening the anges of cans, the combination of a frame, an anvil mounted on said frame for supporting a can, said anvil having a shoulder against which the ilange of the can engages for the straightening operation, a plurality of flange straightening jaws surrounding said anvil, a plurality of support rods slideable in said frame and having their lower ends converging toward each other at an angle to said anvil for supporting said jaws, a cylinder disposed adjacent said rods, a piston disposed within said cylinder and engaging against said rods, and iluid pressure means communieating with said cylinder for moving said piston and the rods engaged thereby for shifting said jaws at an angle to said anvil and into engagement with the flange of the can on said anvil for straightening the ilange against the shoulder on said anvil.

6. In a machine for straightening the iianges of cans, the combination of a frame, an anvil mounted on said frame for supporting a can, said anvil having a shoulder against which the iiange of the can engages for the straightening operation, a plurality of flange straightening jaws surrounding said anvil, a plurality of support rods slideable in said frame and having their lower ends converging toward each other at an angle to said anvil for supporting said jaws, a cylinder disposed adjacent said rods, a piston disposed within said cylinder and engaging against said rods, valve means communicating with said cylinder and with a source of fluid pressure for moving said piston and the reds engaged thereby for shifting said jaws at an angle to said anvil and into engagement with the flange oi the can on said anvil for straightening the flange against the shoulder on said anvil, and spring means acting against said jaws for returning them to release them from said can flange.

7. In a machine for straightening the flanges of cans, the combination of a frame, an anvil mounted on said frame for supporting a can, said anvil having a shoulder against which the ange of the can engages for the straightening operation, a plurality of flange straightening jaws surrounding said anvil, a plurality of support rods slideable in said frame and having their lower ends converging t-oward each other at an angle to said anvil for supporting said jaws, said rods adjacent their lower ends having a web section terminating in laterally extending ledges, a cylinder disposed adjacent said rods, a piston disposed within said cylinder and engaging against the ledges on said rods, said piston having slots conlining web sections of said rods and retaining said rods in position against rotation, and fluid pressure means communicating with said cylinder for moving said piston and the rods engaged thereby for shifting said jaws at an angle to said anvil and into engagement with the flange of the can on said anvil for straightening the flange against the shoulder on said anvil.

HOWARD B. PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,152,437 Rudolphi Sept. 7, 1915 1,719,759 Fink July 2, 1929 1,839,501 Rollason Jan. 5, 1932 

